/*
 * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#ifndef __CSS_SCMI_PRIVATE_H__
#define __CSS_SCMI_PRIVATE_H__

/*
 * SCMI power domain management protocol message and response lengths. It is
 * calculated as sum of length in bytes of the message header (4) and payload
 * area (the number of bytes of parameters or return values in the payload).
 */
#define SCMI_PROTO_VERSION_MSG_LEN        4
#define SCMI_PROTO_VERSION_RESP_LEN        12

#define SCMI_PROTO_MSG_ATTR_MSG_LEN        8
#define SCMI_PROTO_MSG_ATTR_RESP_LEN        12

#define SCMI_PWR_STATE_SET_MSG_LEN        16
#define SCMI_PWR_STATE_SET_RESP_LEN        8

#define SCMI_PWR_STATE_GET_MSG_LEN        8
#define SCMI_PWR_STATE_GET_RESP_LEN        12

#define SCMI_SYS_PWR_STATE_SET_MSG_LEN        12
#define SCMI_SYS_PWR_STATE_SET_RESP_LEN        8

#define SCMI_SYS_PWR_STATE_GET_MSG_LEN        4
#define SCMI_SYS_PWR_STATE_GET_RESP_LEN        12

/* SCMI message header format bit field */
#define SCMI_MSG_ID_SHIFT        0
#define SCMI_MSG_ID_WIDTH        8
#define SCMI_MSG_ID_MASK        ((1 << SCMI_MSG_ID_WIDTH) - 1)

#define SCMI_MSG_TYPE_SHIFT        8
#define SCMI_MSG_TYPE_WIDTH        2
#define SCMI_MSG_TYPE_MASK        ((1 << SCMI_MSG_TYPE_WIDTH) - 1)

#define SCMI_MSG_PROTO_ID_SHIFT        10
#define SCMI_MSG_PROTO_ID_WIDTH        8
#define SCMI_MSG_PROTO_ID_MASK        ((1 << SCMI_MSG_PROTO_ID_WIDTH) - 1)

#define SCMI_MSG_TOKEN_SHIFT        18
#define SCMI_MSG_TOKEN_WIDTH        10
#define SCMI_MSG_TOKEN_MASK        ((1 << SCMI_MSG_TOKEN_WIDTH) - 1)


/* SCMI mailbox flags */
#define SCMI_FLAG_RESP_POLL    0
#define SCMI_FLAG_RESP_INT    1

/* SCMI power domain protocol `POWER_STATE_SET` message flags */
#define SCMI_PWR_STATE_SET_FLAG_SYNC    0
#define SCMI_PWR_STATE_SET_FLAG_ASYNC    1

/*
 * Helper macro to create an SCMI message header given protocol, message id
 * and token.
 */
#define SCMI_MSG_CREATE(protocol, msg_id, token)                \
    ((((protocol) & SCMI_MSG_PROTO_ID_MASK) << SCMI_MSG_PROTO_ID_SHIFT) |    \
    (((msg_id) & SCMI_MSG_ID_MASK) << SCMI_MSG_ID_SHIFT) |            \
    (((token) & SCMI_MSG_TOKEN_MASK) << SCMI_MSG_TOKEN_SHIFT))

/* Helper macro to get the token from a SCMI message header */
#define SCMI_MSG_GET_TOKEN(msg)                \
    (((msg) >> SCMI_MSG_TOKEN_SHIFT) & SCMI_MSG_TOKEN_MASK)

/* SCMI Channel Status bit fields */
#define SCMI_CH_STATUS_RES0_MASK    0xFFFFFFFE
#define SCMI_CH_STATUS_FREE_SHIFT    0
#define SCMI_CH_STATUS_FREE_WIDTH    1
#define SCMI_CH_STATUS_FREE_MASK    ((1 << SCMI_CH_STATUS_FREE_WIDTH) - 1)

/* Helper macros to check and write the channel status */
#define SCMI_IS_CHANNEL_FREE(status)                    \
    (!!(((status) >> SCMI_CH_STATUS_FREE_SHIFT) & SCMI_CH_STATUS_FREE_MASK))

#define SCMI_MARK_CHANNEL_BUSY(status)    do {                \
        assert(SCMI_IS_CHANNEL_FREE(status));            \
        (status) &= ~(SCMI_CH_STATUS_FREE_MASK <<        \
                SCMI_CH_STATUS_FREE_SHIFT);        \
    } while (0)

/* Helper macros to copy arguments to the mailbox payload */
#define SCMI_PAYLOAD_ARG1(payld_arr, arg1)                \
        mmio_write_32((uintptr_t)&payld_arr[0], arg1)

#define SCMI_PAYLOAD_ARG2(payld_arr, arg1, arg2)    do {        \
        SCMI_PAYLOAD_ARG1(payld_arr, arg1);            \
        mmio_write_32((uintptr_t)&payld_arr[1], arg2);        \
    } while (0)

#define SCMI_PAYLOAD_ARG3(payld_arr, arg1, arg2, arg3)    do {        \
        SCMI_PAYLOAD_ARG2(payld_arr, arg1, arg2);        \
        mmio_write_32((uintptr_t)&payld_arr[2], arg3);        \
    } while (0)

/* Helper macros to read return values from the mailbox payload */
#define SCMI_PAYLOAD_RET_VAL1(payld_arr, val1)                \
        (val1) = mmio_read_32((uintptr_t)&payld_arr[0])

#define SCMI_PAYLOAD_RET_VAL2(payld_arr, val1, val2)    do {        \
        SCMI_PAYLOAD_RET_VAL1(payld_arr, val1);            \
        (val2) = mmio_read_32((uintptr_t)&payld_arr[1]);    \
    } while (0)

#define SCMI_PAYLOAD_RET_VAL3(payld_arr, val1, val2, val3)    do {    \
        SCMI_PAYLOAD_RET_VAL2(payld_arr, val1, val2);        \
        (val3) = mmio_read_32((uintptr_t)&payld_arr[2]);    \
    } while (0)

/* Helper macro to ring doorbell */
#define SCMI_RING_DOORBELL(addr, modify_mask, preserve_mask)    do {    \
        uint32_t db = mmio_read_32(addr) & (preserve_mask);    \
        mmio_write_32(addr, db | (modify_mask));        \
    } while (0)

/*
 * Private data structure for representing the mailbox memory layout. Refer
 * the SCMI specification for more details.
 */
typedef struct mailbox_mem {
    uint32_t res_a; /* Reserved */
    volatile uint32_t status;
    uint64_t res_b; /* Reserved */
    uint32_t flags;
    volatile uint32_t len;
    uint32_t msg_header;
    uint32_t payload[];
} mailbox_mem_t;


/* Private APIs for use within SCMI driver */
void scmi_get_channel(scmi_channel_t *ch);
void scmi_send_sync_command(scmi_channel_t *ch);
void scmi_put_channel(scmi_channel_t *ch);

static inline void validate_scmi_channel(scmi_channel_t *ch)
{
    assert(ch && ch->is_initialized);
    assert(ch->info && ch->info->scmi_mbx_mem);
}

#endif    /* __CSS_SCMI_PRIVATE_H__ */
